It is best to say that the protection to properties offered by sea walls along coasts
a.
decreases the present and future risk to human properties
b.
increases both the present and future risk to human properties
c.
decreases the present but increases the future risk
d.
increases the present but decreases the future risk

The best and most correct answer among the choices provided by the question is letter A "decreases the present and future risk to human properties"
A seawall (or sea wall) is a form of coastal defense constructed where the sea, and associated coastal processes, impact directly upon the landforms of the coast.

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